- There are hundreds of trials currently in the works.
- Here’s everything you need to know about the ones edging ahead in the global race.
AS THE WORLD waits eagerly for a Covid-19 vaccine, several candidates are starting to be put through their paces in clinical trials. More than 100 vaccine candidates are being developed by teams around the world, with more than 20 now in or about to enter clinical evaluation, meaning they are being tested in humans.
“When the world got the virus [RNA] sequence through on January 11, we knew pretty well immediately what kind of vaccine one would need and what bit of virus you would need to put in it, so the world of immunology was in a very good state to get going on that,” says Danny Altmann, a professor of immunology at Imperial College London.
On July 20, two vaccine candidates published preliminary results from Phase I and II trials showing they induced an immune response and didn’t trigger any major safety concerns, marking a positive step forward. But there’s still a way to go. Inducing an immune response doesn’t necessarily mean that the vaccine will actually protect people from Covid-19. Only a Phase III trial, which involves giving a large number of people the vaccine and tracking if they get the disease, will show this. “They’ve done everything we wanted, so that’s good news,” Altmann says. “Now it’s the difficult bit.”
The vaccine candidates currently in development make use of a range of different vaccine technology platforms, some of which are tried-and-tested and others that are really cutting-edge. While some first results have started to come out, it’s not possible to draw direct comparisons, as different labs can test with different doses and populations, and use different assays to measure the immune response. “The question of which one is better cannot be answered at this point,” says Beate Kampmann, director of the Vaccine Centre at the London School of Hygiene and Tropical Medicine.